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Old 5th Dec 2012, 09:10
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BEagle
 
Join Date: May 1999
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A330/A340 EAD (AoA PROBES)

An EAD has just been released following an issue experienced by an A330 crew:

The EAD includes the narrative:

An A330 aeroplane experienced a blockage of all Angle Of Attack (AOA) probes during climb leading to Autopilot (AP) disconnection and activation of the alpha protection (Alpha Prot) when Mach number increased.

The blockage of two or three AOA probes at the same angle may cause the Apha Prot of the normal law to activate.
Alors, qu'est que c'est un 'blockage' of an AOA probe? Does that mean blocked with foreign matter / ice / whatever, or is it some quaint Franglais referring to a stuck probe?

The EAD also states:

Under normal flight conditions (in normal law), if the Alpha Prot activates and Mach number increases, the flight control laws order a pitch down of the aeroplane that the flight crew may not be able to counteract with a sidestick deflection, even in the full backward position.
Followed by the "No Sh*t, Sherlock" statement:

This condition, if not corrected, could result in reduced control of the aeroplane.
You don't say!

Another piece of Froggldegook comes in the actual procedure and states:

CAUTION RISK OF UNDUE STALL WARNING
I've heard of spurious stall warnings and have even experienced spurious stall ident and stick push at 500 ft in a much older 4-jet, I've taught 'incipient' stall recoveries and 'fully developed' stall recoveries, but never in 40 years have I ever heard of an 'undue' stall warning....

Just WTF do they mean?
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